Spring Data JPA 建立表的联合主键
Spring Data JPA 建立表的联合主键
https://www.jb51.net/article/159624.htm
最近遇到了一个小的问题，就是怎么使用 Spring Data JPA 建立表的联合主键？然后探索出了下面的两种方式。
第一种方式：
第一种方式是直接在类属性上面的两个字段都加上 @Id 注解，就像下面这样，给 stuNo 和 stuName 这两个字段加上联合主键：
?| 123456789101112131415161718 | @Entity@Table(name = "student")public class Student { @Id @Column(name = "stu_no", nullable = false, length = 11) private Integer stuNo; @Id @Column(name = "stu_name", nullable = false, length = 128) private String stuName; @Column(name = "stu_age", nullable = false, length = 3) private Integer stuAge; @Column(name = "class_id", nullable = false, length = 8) private String classId;} |
| 1234567 | public class StudentUPK implements Serializable { private Integer stuNo; private String stuName; } |
| 12345678910111213141516171819 | @Entity@IdClass(StudentUPK.class)@Table(name = "student")public class Student { @Id @Column(name = "stu_no", nullable = false, length = 11) private Integer stuNo; @Id @Column(name = "stu_name", nullable = false, length = 128) private String stuName; @Column(name = "stu_age", nullable = false, length = 3) private Integer stuAge; @Column(name = "class_id", nullable = false, length = 8) private String classId;} |
这样就能成功的创建表了，而且在使用 JpaRepoistory 的时候，可以指定主键为那个 StudentUPK 类，就像这样：public interface StudentRepository extends JpaRepository
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持脚本之家。